Calorie Calculator
Estimate daily calorie needs using Harris-Benedict and Mifflin-St Jeor equations. Adjust for activity level and goals. Free, 100% in your browser.
Reference
How are daily calories calculated?
Your daily calorie needs depend on your Basal Metabolic Rate (BMR) — the energy your body burns at rest — multiplied by an activity factor. Two widely used equations estimate BMR: the Harris-Benedict equation (1919, revised 1984) and the Mifflin-St Jeor equation (1990). Mifflin-St Jeor is generally considered more accurate for modern populations. Both use gender, age, weight, and height as inputs.
BMR formulas
Mifflin-St Jeor:
Male: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161 + 166
Female: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
Harris-Benedict (revised):
Male: BMR = 88.362 + 13.397 × weight(kg) + 4.799 × height(cm) − 5.677 × age
Female: BMR = 447.593 + 9.247 × weight(kg) + 3.098 × height(cm) − 4.330 × age
Activity multipliers: Sedentary = 1.2, Light = 1.375, Moderate = 1.55, Active = 1.725, Very active = 1.9.
Common use cases
- Weight loss — a deficit of 500 kcal/day leads to approximately 0.45 kg (1 lb) loss per week.
- Weight gain — a surplus of 500 kcal/day supports muscle building when combined with resistance training.
- Maintenance — knowing your TDEE (Total Daily Energy Expenditure) helps maintain current weight.
- Meal planning — distribute daily calories across meals and snacks for balanced nutrition.
- Fitness tracking — compare calorie intake vs. expenditure to stay on target with your goals.
Privacy
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